Ubuntu 23.10 boot from Open ZFS

I tried out the ZFS install option om a VM and Tuesday I decide to use ZFS for Ubuntu 23.10. I used the default minimal install, since I moved all my apps to specialized VMs. The installer did take my whole 512GB nvme, so now it has

  • 1.1GB boot/efi partition;
  • 2.1GB bpool partition for the ZFS boot;
  • 4.3GB SWAP partition and
  • 505GB rpool partition for Linux and any other stuff. The Linux installation only needs 4.61 GiB, see also the conky display. I also restored my 10 main VMs from a backup to a vbox dataset.

Note that all ZFS partitions are lz4 compressed by default. Sofar the system works without any issue, I even dual boot with Ubuntu 22.04 LTS on a 2TB MBR HDD.

This installation of ZFS is much simpler and thus better than the previous too complex version (KISS). It just installs the system. You yourself has to manage the snapshots, so I have 3 simple script to do it; snapshot; destroy and rollback. The -r means recursive and includes all lower level datasets. The create looks as follows;
zfs snapshot -r bpool/BOOT@$1
zfs snapshot -r rpool/ROOT@$1
zfs list -t snapshot | grep OOT

For the VMs I take a snapshot every Saturday and I probably will do the same for the BOOT and ROOT system. Worst case you have to rerun one week of updates. If you use the /home directory often, you might consider doing it more frequently. Personally I use a separate zfs datasets for my data and VMs.